Review: Grand Seiko Tentagraph SLGC001

The Grand Seiko Tentagraph is just begging to be compared to the Rolex Daytona. Not just because it’s a chronograph, or because Grand Seiko has eyes for Rolex’s lunch—but because it costs within £200 of the famed Rolex chronograph. Now, I know buying the Daytona at RRP is harder than old cheese at zero degrees, but someone, somewhere is going to be faced with the decision of buying one over the other. John, of 231 Signet Drive, Oklahoma, this is for you.

Background

How did we get to a £12,500 Grand Seiko chronograph? Well despite Grand Seiko only knocking about since 1960, it took until 2007 to make a chronograph. No, that’s not because they don’t have eggs that need timing in Japan—they do—it’s because the first Grand Seiko chronograph was Spring Drive.

To the uninitiated, Spring Drive sounds like, well, basically any other watch movement, because virtually all mechanical wristwatch movements are driven by a spring. See how I said virtually all so you can’t catch me out with that one watch made by that one guy I’ve forgotten. Smart, me.

Nope, Spring Drive is a whole other kettle of fish. Putting it simply, it’s a quartz movement powered by a spring instead of a battery, like those radios you can crank into life. Sounds straightforward. It really wasn’t. Let me read you an excerpt from the history of Grand Seiko to set the scene.

1978 - Filed a patent for the Spring Drive mechanism for the first time. 1982 - Filed a patent for the Spring Drive mechanism for the second time. Started initial development. 1993 - Started the second development of the Spring Drive. 1997 - Started the third development of the Spring Drive. 1998 - Had lunch. 1999. Released the Spring Drive.

It took over twenty years to develop Spring Drive because it’s basically witchcraft. And so by the time Grand Seiko managed to wrangle it into a chronograph movement in 2007, they were very, very pleased with themselves. But there was a problem. Some might say a big problem. The Spring Drive Chronograph had looks even a mother might question.

The Spring Drive Chronograph has always been an expensive watch. It starts at nearly £8,000. I suppose the thing that’s changed is that everything else has caught up with it, so now it doesn’t seem quite so bad anymore. But the looks remain challenging, and so at the beginning of 2023, Grand Seiko added another diary note to the ongoing list: Released the Tentagraph.

What is the Tentagraph? It’s not Spring Drive for a start. It’s based around the 9S calibre first seen in 2020, complete with high-beat 36,000vph rate and extended power reserve of 72 hours, thanks to the ingenious dual impulse escapement. To put that into context, usually if you want a faster beat, ten per second over eight, you have to sacrifice power reserve because you’re asking for 25% more work.

So, for example, a similarly fast El Primero movement with the same ten beats per second will run out after 60 hours. That’s why Rolex, when it pinched the El Primero for the Daytona 16520 in 1988, detuned it back to 28,800vph.

Grand Seiko had its saké and drank it too by, you know, completely reinventing the mechanical wristwatch. Now, being typically Japanese, Grand Seiko doesn’t like to brag about it, but basically they found an extra 25% efficiency by creating a new escapement that drives the balance wheel directly from the escape wheel every other beat. The performance increase is so tremendous that if watchmaking were still a competitive sport, they’d be accused of cheating.

Why would a chronograph even need ten beats per second instead of eight? It’s not really too relevant in your typical watch, but in a chronograph, where fractions of a second are measured, a tenth actually makes sense. Other chronographs at 28,800vph can only measure to an eighth of a second. And who’s ever heard of one-eighth of a second? That’s basically useless.

Review

So, Tentagraph. It’s a chronograph, but with, like, ten. Yeah, that’s not a joke. That’s why it’s called the Tentagraph. Obvious tentacle puns aside, while it’s not the physics defying tech-fest of the Spring Drive Chronograph, it is still a very impressive device. The whole idea of developing an outdated technology to such extremes is what makes Grand Seiko so appealing. The fact the Tentaclegraph—sorry, Tentagraph—looks so good also helps.

The 9S-series watches are a big step up from previous generation Grand Seiko watches, both inside and out, introducing a level of detailed finish that rivals Swiss brands that you might consider to be several steps higher. But that £12,500 price sets it up squarely against the Daytona, so that’s where we’ll pitch it.

Both have 100m of water resistance, but the Grand Seiko manages it without screw-down pushers. Both have a power reserve of 72 hours, although as I mentioned, the Daytona ekes its out by sacrificing two beats per second. The Grand Seiko gets an impressive accuracy of -3/+5 seconds per day from the calibre 9SC5, although the Daytona beats that at -2/+2 seconds. Ceramic bezels adorn both, with the Tentagraph’s a spit for the £590 Seiko Speedtimer’s.

Where the specs begin to deviate is in the case. You get 40mm in steel for the Daytona, 43.2mm in titanium for the Grand Seiko. It’s also 15.3mm thick compared to the Rolex at just 12.4mm. Yeah. The Tentagraph is a big, big watch. For some prospective buyers, that’s where the interest ends. Game over. Do not pass go. Because if it’s too big for you, it doesn’t matter how much you love it, it’s not going to work.

That’s where Rolex have been most clever, making the Daytona work so well over so many wrist sizes. I do believe it actually measures slightly smaller than 40mm in real life, further adding to its universality. The Tentagraph requires someone more impressive of wrist to make it work. I have a 7-inch wrist and I think I get away with it. Short lugs help, and the titanium stops it feeling top heavy.

Rolex of course have a fantastic clasp that Grand Seiko has chosen not to bother competing with. I know that really bothers some people, although I think the Tentagraph belongs on a strap. It has that feel to it, like basically every Grand Seiko.

So why consider the Grand Seiko at all? Let’s go back to that finish. The dial borrows the chunky 9S handset and compliments it with a set of chronograph sub-dials, a deep sunburst finish and impeccable execution. The Rolex is very well made and nicely crisp, but this feels a league above. That’s been Grand Seiko’s calling card for a long time, and the Tentagraph far from disappoints.

The case is magnificently sculpted in ways that make you wonder how they even did it at all. Finishing one of these things must be like one of those puzzles where you have to shuffle all the pieces about but there’s only ever one spare space to shuffle them into. It’s like in the design briefing, in response to the question, “How many facets should the case have?” the answer was, “Yes.”

Where we really get to feel like we’re playing a different game entirely is with the calibre 9SC5. It looks like the chronograph element must be modular because the view is no different to the time-only 9SA5 through the back—and that would explain the thickness—but boy what a view it is. This is proper watchmaking, boys and girls, and you don’t have to pay £50,000 to see it like you do in the Daytona.

When you can actually see it, the Rolex’s calibre looks like a much simpler device. There’s less sculpting, less shaping. Details like the rotor weight lack the Grand Seiko’s level of detailing. It’s definitely much more of a workhorse calibre by comparison. I would realistically sit the Tentagraph’s 9SC5 equal to or perhaps even a bit higher than Jaeger-LeCoultre’s Polaris Chrono—which costs another thousand pounds again. Maybe—maybe—even near Blancpain’s Bathyscaphe Chrono.

So, the outcome. Should you buy the Daytona over the Grand Seiko? Yeah, obviously, at RRP. No question. Why are you even still here? The real conundrum is should you keep that Daytona or flip it for the Grand Seiko? That’s a harder one to answer. It’s good. Very good. If it fits, that is. As with all Grand Seikos, it still presents good value, but perhaps not to the extremes we’ve seen in the past. It’s very trick and impeccably finished, but it is still a £12,500 watch, and faces very stiff competition. You’ve really got to want it. But if you do, there’s nothing else quite like it.

What do you think of the Grand Seiko Tentagraph?

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